UPDATE: I have now posted some additional thoughts about this issue.
It's been a frustrating time here at the hotel in Ontario, CA, where all I've been trying to do is use the Internet connection. I'm staying at the Best Western and did so largely because they advertised free high-speed Internet (they were also cheaper than others). First annoyance was discovering that I was too far away from their APs to use wireless, but since I had an ethernet cable I just plugged into the wall jack and expected to get access. The very first time I connected, I did get an IP address and could see an entry in my routing table for the default gateway. However, I couldn't ping it.
Being rather used to network troubleshooting, I did the usual things... bringing the interface up and down, disconnecting and re-connecting the cable. I even went to the hotel lobby and got a new cable in case the issue was with my portable/retractable cable.
Nothing. No net.
In desperation I did the thing that tech support always tells you to do but I avoid... reboot. Nothing.
So finally this morning I got on the phone to the Best Western tech support and after waiting, oh, 20 minutes or so I got through to a tech and ultimately we figured out the problem:
More specifically, all the bizillion connections that Skype was making out into the P2P cloud. The tech reset the switch and asked me to connect again and his immediate response was "Whoa! Something on your computer is generating an incredible number of sessions out to the Internet! You are tripping our filters and it is blocking out your MAC address." With him on the phone, we tried some experimentation. I shut down Skype, at which point he said I was generating much more normal traffic. As soon as I launched it again, he noticed a very large jump in the number of session connections I was establishing. He said it was something like 396 sessions he was seeing coming from my computer. He also said that I'll keep being locked out of their system if I keep Skype running.
So I shut down Skype. Which, of course, is annoying. Part of why I wanted to use the high-speed Internet is to use Skype for IM and for voice/video calls.
I find it a bit odd that Skype was generating so much extra traffic, but then again I am pretty much always connected into several persistent group chats and had maybe 8 or 10 individual chat windows still open that I'd left open from when I'd last been chatting with the person. (The Mac Skype client makes this easy to do, but I'll write about that sometime.) The persistent group chats, especially, do generate a good number of connections as they link out into the P2P cloud. Perhaps if I closed all of those windows and killed off all my individual chat windows Skype might have behaved better. (Or perhaps not, I might have had to leave the persistent chats in order for Skype to stop making those connections.) I don't want to try it out, because I do want to keep my Internet connection up right now.
In any event, should you be at a hotel and find yourself unable to connect... it might be a P2P app like Skype tripping off the hotel's filters and blocking your access. Fun, fun, fun....